Improvement in drilling-machines



ATENT N WILLIAM H. THORNE, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN DRlLLlNG-MACHINES.

Specilcation forming part of Letters Patent No. 139,629, dated June 3, 1873; application led February 24, 1873. A

To all whom it may concern:

Beit known that I, WILLIAM H. THORNE, of `the city and county of PhiladelphiaJ and State of Pennsylvania, have invented certain Improvements in Radial Drilling-Machines, of which the following is a specication:

i The first part of my invention relates to the combination of cone-pulleys, bevelgearing, and grooved shaft with the base-plate, post, and radial arm of a radial drilling-machine, in such a manner that motion can be transmitted from the cone-pulley to the drillingspindle when the drilling-spindle is in different `positions on the radial arm, and when the radial arm is pointing in different directions; the objects of this part of my inveny tion being to place the cone-pulleys in a position convenient for the operator, and to reduce the parts necessary to transmit motion to the grooved shaft. The second part of my invention relates to the combination of a table lfor holding the thing to be drilled with the post or column and the radial arm carrying the drilling-head in such a manner that the table can be raised or lowered on the post; the objects of this part of my invention being to permit the table to be adjusted at the proper distance from the drilling-spindle to suit the thickness of the thing to be drilled, and at the same timereducing the leverage between the table and the drilling-spindle, and thus making the stitfest and strongest arrangement possible. The third part of my invention relates to the combination, with the drilling-spindle and saddle or bearing sliding on the radial arm, of a weighted lever, in such a manner that the weight of the spindle is always counterbalanced and held up close against the feeding device, no matter in what position the saddle may be on the radial arm the object of this part of my invention being to prevent the breaking of drilling-tools, which are held in the end of the spindle, in event of the spindle dropping a little when a hole is almost Iinished and the resistance withdrawn from the cutting-edge of the tool in a portion of its revolution. The general object of the invention is to produce a radial drilling-machine havin g all the conveniences and adjustments of stationary drilling-machines.

Figure l is a4 front elevation, showing the general arrangement. Fig. 2 is a side elevation. Fig. 3 is a plan, showing a section on the line a, b in Fig. l, and the parts below that line.Y Fig. 4 is a side elevation, to an enlarged scale, of the weighted lever and` its connections With the drilling-spindle. Fig. 5 is a front elevation and partial section of the same. Fig. 6 is a plan of a modification of the post and table.

A is the post of the machine, which post is of .cylindrical form, turned and fitted to the` radial arm D, and carrying on its top the conepulley F, on the shaft of which is the bevelpinion K. The bevelgear wheel M turns freely on a stud heldon the top of the post A, y in line with its axis. The post A, below the sleeve of the radial arm D, has on one of its sides a dat bearing with V-shaped projections,

which is fitted to a corresponding llat bearing with V-shaped recesses on one end of the table B, so as to permit the table B to beraised and lowered on the post A. Another method is to pass the post A directly through one end of the table B, as shown in Fig. 6. The means employed for raising and ,lowering the table B are the same as those ordinarily used on stationary drilling-machines, being either a screw or a rack and pinion, operated by suitable mechanism. The post A is fastened to a base-plate, C, which carries a bearing, in which revolves the shaft carrying the cone-pulley H and pulley Y, to which motion is given.

-The radial arm D turns freely around the post A, and carries with it a bearing, d, in which the grooved shaft N revolves. The bevel-pinion L revolves with the shaft N, and isdriven by the bevel-gear M. The grooved shaft N transmits motion to the gearing for revolving the spindle, which is carried by the bearing or saddle I. The saddle I slides on the radial arm D. The drilling-spindle P has screwed onto the upper end of it a yoke, T. 'I he feedscrew X has a collar on its end, the upper side of which bears against the yoke T, and the lower side against the end of the spindle P. W is a lock-nut to prevent the yoke T from turning on the spindle P. The yoke T is cylindrical, and is tted loosely to the collar V, which is pivoted to the light end ofthe weighted lever R. The weighted lever R is supported by the fulcrum S, which is carried by the met.,

saddle I. Motion is given to the. pulley Y, and is transmitted from the cone-pulley H to the cone-pulley F, by means of a continuous band or belt, which is thus placed so as to be conveniently shifted by the operator from one step of the cone-pulleys to another in order to change the speed. As the bevel-wheel M rotates on the same axis as the radial arm D, and as the radial arm D carries the bevelpinion L and grooved shaft N, it must follow that motion will be transmitted from the bevelpinion K by means of the bevel-Wheel M to Y* the bevel-pinion L and grooved shaft N, in

Whatever direction the radial arm D may be pointing, excepting such as would bring the bevel-pinion L in contact with the bevel-pinion K. The table B, being fitted to the post A so as to raise and lower thereon, has a vertical adjustment to suit the thickness of the work being drilled. This makes a muchstronger and stil'er arrangement than where the table rests on the baseplate alone. As the light end of the weighted lever R is pivoted to the collar V, which bears up against the yoke T, which is rmly xed to the spindle P, it is evident that the upper end of the spindle P will always be kept close against the end of the feeding-screw or rack, as the case may be, and thus prevent the bad effects arising from any lost motion that would occur from wear. The weighted lever R being hinged to the fulcrum S, which is hinged to the saddle I, will support the spindle P, no matter in what position the saddle I may be on the radial arm D.

I claim as my inventionl. A table, B, having vertical adjustment on the standard, in combination with the horizontally-swinging arm D, the sliding saddle and drill, andthe mechanism for rotating said drill, substantially as shown and described.

2. In combination with a radially-swinging arm and adjustable drilling-head and spindle,

the Weighted lever It, or its equivalent device, n

substantially as and for the purposes set forth.

WM. H. THORNE.

Witnesses J oHN C. DU COSTA, Jr., I. N. DE HAVEN. 

